I. Field of the Invention
The present invention relates to fueling systems for automotive vehicles and, more particularly, to a capless automotive fueling system.
II. Description of Related Art
All automotive vehicles include fueling systems to allow the fuel tank for the vehicle to be refilled. Typically, the fueling systems include a funnel which is dimensioned to receive a conventional fuel filling nozzle. The funnel in turn is connected to the fuel tank for the vehicle.
Many of these fuel filling systems also include an orifice inserted into or formed in the funnel which is dimensioned to receive the neck of the fuel filling nozzle. A spring loaded flapper valve is oftentimes mounted to the funnel and movable between an open and a closed position. In its closed position, the valve closes the port in the fuel funnel to trigger a premature shutoff of a too-large diameter nozzle tip by blocking the majority of the fuel flow. Conversely, upon insertion of the fuel filling nozzle into the port, the nozzle moves the fuel valve to its open position to allow the fuel tank to be filled in the conventional fashion.
Current government regulations, conventionally known as the Clean Air Act, restrict the amount of fuel vapors that may escape from the fuel system for environmental reasons. Such government regulations, furthermore, increasingly restrict the amount of fuel vapor escape from the automotive fuel system over time.
For this reason and to prevent contaminants from entering the fuel tank, the previously known automotive fueling systems include a gas cap which is secured over the open end of the funnel following a refueling operation. However, the failure of the vehicle operator to secure the gas cap onto the fuel filling funnel with sufficient torque will cause insufficient sealing between the fuel funnel and the gas cap. When this occurs, fuel vapors from the gas tank in excess of that permitted by governmental regulations escape past the gas cap and, for newer North American market vehicles, activate a warning light for the vehicle operator.
When such a warning light is illuminated for the vehicle operator, the vehicle operator oftentimes returns the vehicle to the vehicle dealer or other maintenance facility only to discover that the only vehicle “malfunction” is that the gas cap has been too loosely installed on the vehicle. This presents not only an inconvenience for the vehicle operator, but a major warranty expense for the automotive vehicle manufacturer.
A still further disadvantage of the conventional fuel filling systems for automotive vehicles is that the flapper valve which closes the funnel port is freely movable between an open and a closed position. This flapper valve is moved to its open position upon the insertion of a fuel nozzle.
Fuel nozzles have standardized diameters depending on the type of the fuel. For example, a fuel nozzle for unleaded gasoline has a first diameter while a fuel nozzle for diesel fuel has a second and larger diameter.
Furthermore, the size of the fuel port in the fuel funnel assembly is dimensioned for the type of fuel utilized by the engine. Consequently, since the fuel nozzle for diesel fuel has a larger diameter than the fuel nozzle for unleaded gasoline, the fuel nozzle for diesel fuel cannot be inserted into the fuel funnel assembly for a vehicle which utilizes unleaded gasoline.
Unfortunately, the converse is not true. Instead, since the fuel nozzle for unleaded gasoline is smaller in diameter than the fuel nozzle for diesel fuel and also since the fuel flapper valve is freely pivotally mounted to the fuel funnel assembly, it is possible to inadvertently fill the fuel tank of a vehicle having a diesel engine with unleaded gasoline. This, in turn, results in damage if not destruction of the engine.
In one prior art device flexible latches engage and retain the fuel valve in a closed position. Upon insertion of a properly sized fuel nozzle, the fuel nozzle engages the latches and flexes the latches outwardly to disengage from the fuel valve and allow the fuel valve to open. However, repeated flexing of the latches can result in weakening or even breakage of the latches thus rendering them inoperable.